Speech Generating Device - History

History

SGDs have their roots in early electronic communication aids. The first such aid was a sip-and-puff typewriter controller named the patient-operated selector mechanism (POSSUM) prototyped by Reg Maling in the United Kingdom in 1960. POSSUM scanned though a set of symbols on an illuminated display. Researchers at Delft University in the Netherlands created the lightspot operated typewriter (LOT) in 1970, which made use of small movements of the head to point a small spot of light at a matrix of characters, each equipped with a photoelectric cell. Although it was commercially unsuccessful, the LOT was well received by its users.

During the 1970s and early 1980s, several companies began to emerge that have since become prominent manufacturers of SGDs. Toby Churchill founded Toby Churchill Ltd in 1973, after losing his speech following encephalitis,. In the US, Dynavox (then known as Sentient Systems Technology) grew out of a student project at Carnegie-Mellon University, created in 1982 to help a young woman with cerebral palsy to communicate. Beginning in the 1980s, improvements in technology led to a greatly increased number, variety, and performance of commercially available communication devices, and a reduction in their size and price. Alternative methods of access such as eye pointing, where the movement of a user's eyes is used to direct an SGD, and scanning, in which alternatives are presented to the user sequentially, became available on communication devices. Speech output possibilities included both digitized and synthesized speech.

Rapid progress in hardware and software development continued, including projects funded by the European Community. The first commercially available dynamic screen speech generating devices were developed in the 1990s. Software programs were developed that allowed the computer-based production of communication boards. High-tech devices have continued to become smaller and lighter, while increasing accessibility and capability; communication devices can be accessed using eye-tracking systems, perform as a computer for word-processing and internet use, and as an environmental control device for independent access to other equipment such as TV, radio and telephones.

Notable individuals who have used AAC devices include Stephen Hawking, Roger Ebert and Tony Proudfoot. Hawking is unable to speak due to a combination of severe disabilities caused by ALS, and an emergency tracheotomy. He has come to be associated with the unique voice of his particular synthesis equipment.